Regulating system for alternating current circuits



Och 1933- J. KUBLER 1,930,979

REGULATING SYSTEM FOR ALTERNATING CURRENT CIRCUITS Filed Dec. 11, 1930 lllllll III...

lllllll IIIIIII Johannes Kubler Attorney I Patented Oct. 17, I I

UN T

-REGULATING'QSYSTEM' FOR ALTERNATING T l If 9 CURRENT CIRCUITS I J ohannesQKubler Baden, Switzerland, assignor 7 I to Aktienges'ellschaft Brown, Boveri & Cie,

Baden, Switzerlan d, a' joint -sto'ck company of f Application December 11, 1990, Serial No. 501,551, i i and in Germany December ,2, 1929 I I '4 Claims] (01. 172-1238) This inventionrelates to voltage regulating systems wherein both-theangle and the magnitude of the voltage vectorof the several phases f of a. polyphase alternating current line are regu- 5 lated. V I e The present invention provides an arrange 'me'ntby which the angle and magnitude of. the voltage vector of ajpolyphase line may be'simultaneously regulatedor may be' regulated in sel quencek" Briefly stated;-the delta connected sec- I onda'ry windings 'of a transformer are tapped. at

the midpoint. In one embodiment of the invention, series regulating transformers are connected to themidpoints and the corner points of the l windings to be regulated to regulate the angles and the magnitude of the voltage vector; the primary of the transformer regulating the angle of the voltage vector being connected across one of the phases to be regu1ated, 'the primaryofthe 29 transformer regulating. the magnitude of the voltage vector being connectedwwith the mid-- 35 The invention will be readily comprehendediby,

reference to the accompanying drawing; when read "in connectionflwith the'following description, in which drawing Figure 1'.diagrammaticallyillustrates one embodiment of the'present invention," Fig. 2 shows a simplifiedmodification of the present invention, and 1 Fig. 3 shows the vector relations of the several phases obtaining in the embodiment according toFi'gurelt Referring to the drawing by' -ch'aracters of reference, the reference numeral "6 designates a polyphase alternating current supply line, connected with the 'prima ry winding '7 of'atransseveral phases thereof are indicated at 811, 8b and 8c. The corner connection points of the several phases of the secondarywinding 8 are designated'at 9, 10 and 11 and each of the phase former}to beregulatedi The secondary winding '8 of the transformer is delta connected and the windings 8a, "Sb'and 8c are tapped at their're spectivefmidpoints- I Apair of seriesconnected regulating trans formers 14, 15; 16, 17; 18, ,19 are connected with the secondary winding B'for the purpose of reg"u lo lating the phases 8a, 8b andSc respectively. [The transformers 14,16 and 18 are arranged to regulate the magnitudeof the phase voltage vectors and transformers 15, 17 and 19 arearranged to regulate the angles of the phase voltage vec- '55 tom of the several phases; The secondary windings of allof-the regulating 'transform'ers'are Y adjustable and are connectedin series with an alternating current feeder line designated at '21.

The arrangement and connections of each pair of the-regulating transformers is the transformers for regulating themagnitude and the I phase angleof the voltage-vector being similar, ihe connections of only onepair of the transformers namely the-transformers 14 and 15iwill I be described in detail. Considering the connec-- t-ions of the transformer 14, the primary winding thereof is connected between "the midpoint of the phase 8c and the corner point 9 of the secondary winding 8 which corner point is opposite the "g0 midpoint of the winding8c. The primary winding of the phase angle regulating transformer 15 is connected across the phase ofthe secondary winding 8 at the corner points 10 and llf One end of the secondary-winding; of the transformer 8'6 '14 is-connected withihe'corner-point 9 of the rnain secondary windings'and is adj ustablyconneeded with the secondary' wifnding of the trans- Y former :15 which is itself I adjustably connected I with one phase conductorof the polyphase feeder 13D line21.*' a

I Regulation of the angle of the voltage vector' of the phase 8b will now be described in detail,

jittbeing understood that the'various' portions of f I theStructure shown cooperate to secure regula- '95 tion of the vectors of the oth'er'phases in a similar manner. 7 Regulation ofthe angle voltage vector of the phase- 8!) is obtainedby adjust- "mentfof the secondaries ofthe transformers 1'5 4 and lTwhich regulation'slightly varies the mag- F109 niture of thecorrsponding voltage :vector; The magnitude of the voltage vector isthen regulated by; adjustment of the secondaries of the, trans-v formers ,1 4Iand 16 which are, connected iin series with the secondaries of the transformers 15 andr lb5 17. It will be understood that the secondaries of the transformers 14, 16'and'18 as well as the secondaries of the transformers 15,17 and 19 are simultaneously adjustable to secure proper regulation of both the angle and the magnitude of the P10 voltage vectors of all phases of the secondary winding 8.

The relations of the several voltage vectors may readily be seen from the vector diagram shown in Fig. 3 which illustrates both the angle and magnitude relations ofthe several phases. The angle of the vector of the phase 81) is regulated by the simultaneous or sequential regulation of the secondaries of the transformers 14, 16 and 15, 17. Tracing the diagram shown in the direction of the arrow-heads thereon marked b, it will be seen that the magnitude vectors 14 and 16 when plotted relativefto the vector 8b will yield a resultant 8hr which is less than the former vector 8b and the angle vectors 15 and 17 when plotted relative to the angle vector 8b will yield a resultant angle vector 8171' which differs in direction from that of the original angle vector 81). Reference to the other portions of the vector diagram of Fig. 3 will show that the vector relations of the other phases are similarly adjustable and are similarly changed by the same operation of adjustingthe secondaries, of .the regulating transformers.

In the embodiment shown in Figure'Z, the pri mary windings of the magnitude vector regulating transformers 14, 16 and 18 are connected to a corner point of the secondary winding 8 opposite the phases to be regulated by each pair of regulating transformers and are likewise connected to the midpoint of the angle voltage vector regulating primary windings of the transformers 15, 17 and 19 which are ihemse'ives connected across the midpoints of, the phases of the secondary winding 8 to be regulated. The connections required are thus simplified and the voltages on the primary windings of the regulating transformers are reduced; to one-half of the values present on the same winding'when connecied as shown in Fig. 1 thus greatly simplifying and reducing the insulation required in the regulating transformers. I

Although but two embodiments of the present invention have been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.

The invention claimed is: i

1. In a system for regulating alternating current circuits, incombination with a polyphase line, and a transformer having mid-tapped delta connected phase windings operative to impress potentials on the phase conductors of said line, of means operative to regulate the phase angles of the said phase conductors of said line comprising a transformer for each phase conductor having a secondary winding serially connected in circuit between its associated phase conductor and an end terminal of its associated said delta connected winding, and a primary winding connected with the end terminals of another of said delta connected windings, means operative to regulate the magnitude of said potentials comprising a transformer for each of said phase conductors having a secondary winding serially connected in circuit between its associated phase conductor and an end terminal of its associated said delta connected winding, the primary winding of each of the last said transformers being connected with an end terminal of its associated delta connected winding and the mid-point tap of another of said delta connected windings, each or said secondary windings being provided with taps, and means operative to selectively vary the connections to said taps to thereby vary the effective turns of said secondary windings.

2. In a system for regulating alternating current circuits, in combination with a polyphase line, and a transformer having windings operable to impress potentials differing in phase angle on the respective phase conductors of said line, of means operable to regulate the phase angle and the magnitude of the potentials impressed on said conductors comprising a plurality of transformers for each said conductor having secondary windings connected in series therewith and primary windings impressed with potentials of the same frequency as the frequency of the potential impressed upon the associated one of said conductors with respect to the potentials impressed on the others of said conductors by the first said transformer but differing therefrom in phase angle, each said secondary winding being provided with a plurality of tap connections, and means operable to selectively vary the connections to said taps to thereby vary the effectiveturns of said secondary windings.

3. In a system for regulating alternating current circuits, in combination with a polyphase line, and means operable to impress potentials differing in phase angle on the respective phase conductors of said line, of means operable to regulate the phase angle and magnitude of the potentials impressed on said conductors comprising a plurality of transformers for each said conductor having secondary windings connected in series therewith and primary windings impressed with potentials of the same frequency as the frequency of the potentials impressed upon the associated one of said conductors with respect to potentials impressed on the others of said conductors by the first said means but difiering therefrom in phase angle, and means operable to vary the ratio of transformation between said such as to induce in the respective said secondary windings voltages differing in phase angle by 90 electrical degrees from each other and each differing in phase angle from the voltage impressed on the associated said conductor by the first said means with respect to the voltages impressed therebyon the others of said conductors, and means operable to vary the ratio of transformation between said secondary windings and the associated said primary windings.

JOHANNES KUBLER. 

